The genetic fallacy creates a fallacious argument that is accepted or rejected based on the source of the evidence, rather than on the quality or applicability of the evidence. It is also a line of reasoning in which a perceived defect in the origin of a claim or thing is taken to be evidence that discredits the claim or thing itself. The fallacy is committed when an idea is either accepted or rejected because of its source, rather than its merit.

The genetic fallacy is a logical fallacy but is frequently not a Bayesian one: some sources are so consistently full of it that they reasonably constitute a refutation for all practical purposes. However, that this is a logical fallacy means you will still need to convince the source's fans and bystanders by engaging the source material.

Contents

Note that there are cases where this type of argument may not be fallacious. For example, there are some cases in which the origin of a claim is relevant to the truth or falsity of the claim, such as a claim that comes from a reliable expert is likely to be true (provided it is in her area of expertise).